Use stored username and password while querying index from frontend

[smadha]

For filling popup data we query index from frontend.

Index might require username and password for access.

username and password is stored in admin core which can be used to query index from frontend as we do it from backend.

as of now a popup comes on screen per session, asking user for entering username and password

[smadha]

@chrismattmann apart from this use case geoparser will use stored username and password for querying index